scholarly journals Effect of the Polymerized Titanium Ferric Sulfate (PTFS) Coagulant on Sedimentation of Coal Slime Water

Minerals ◽  
2021 ◽  
Vol 12 (1) ◽  
pp. 26
Author(s):  
Changsheng Shi ◽  
De Guo ◽  
Yang Li ◽  
Zhenxing Zhang ◽  
Ligang Tang
Keyword(s):  
High Efficiency ◽  
Ferric Sulfate ◽  
Raw Material ◽  
Molar Ratio ◽  
Coal Preparation ◽  
Polyaluminum Chloride ◽  
Molar Ratios ◽  
Titanium Sulfate ◽  
Before And After ◽  
Coal Slime

High efficiency slime water settlement is very important for ensuring washing water recycling in coal preparation plants. In order to improve the sedimentation of coal slime water, an iron ion-based coagulant was prepared by titanium ion complexation action using titanium sulfate as a main raw material, Fe3+ and NaH2PO3 as a stabilizer and NaHCO3 as an alkalizing agent. The particle size distribution of coal slime was measured, and the sedimentation test for coal slime water was carried out with PAM, polyaluminum chloride and polymerized titanium ferric sulfate (PTFS), respectively. Then, coal slime water sedimentation was investigated at different PAM dosages and polyaluminum chloride or coal slime water of PTFS with various molar ratios of PAM and ferrotitanium. The results showed that PAM and polyaluminum chloride could not make coal slime settle down, and PTFS showed a poor settlement effect. When polyaluminum chloride and PTFS were used together with PAM, it produced a molecular weight of 3 million respectively. Polyaluminum chloride needs 6.66 × 10−10 mol of PAM, PTFS needs 0.66 × 10−10 mol of PAM and the effect of sedimentation is improved. When the molar ratio of PTFS was 1:7, polymerization performance was effective. The sedimentation effect of PTFS was better than that of polymeric aluminum chloride coagulant usually used in coal preparation plants, especially when combined with flocculant, and high efficiency was reached. The surface potential and surface free energy of coal slime particles before and after adding coagulant were measured and analyzed by XDLVO theory to explain the action mechanism of PTFS coagulant. Experimental results demonstrated that PTFS can significantly improve the sedimentation of coal slime water, save the dosage of PAM and increase economic benefit.

scholarly journals Red Mud-Based Polyaluminum Ferric Chloride Flocculant: Preparation, Characterization and Flocculation Performance

2021 ◽  
Author(s):  
Yong Cheng ◽  
Longjun Xu ◽  
Chenglun Liu ◽  
Zao Jiang ◽  
Qiyuan Zhang ◽  
...  
Keyword(s):  
Red Mud ◽  
High Efficiency ◽  
Low Cost ◽  
Oxygen Demand ◽  
Industrial Applications ◽  
Iron Chloride ◽  
Raw Material ◽  
Molar Ratio ◽  
Polymerization Temperature ◽  
Solution Ph

Abstract In this work, red mud was used as raw material to extract Al and Fe with hydrochloric acid. The high-efficiency polyaluminum iron chloride (PAFC) flocculant was prepared via adjusting the pH of the leaching solution, the molar ratio of aluminum and iron, and the polymerization temperature. The effect of synthesis and flocculation conditions on the flocculation performance of aged landfill leachate was investigated. The results confirmed that the PAFC prepared at the polymerization pH of 2.5, the Al/Fe molar ratio of 8, and the polymerization temperature of 70 °C had the optimum flocculation effect. The flocculation consequences of PAFC and commercial polyaluminum iron chloride flocculant (CPAFC) under different flocculation conditions were compared. The chemical oxygen demand (COD), UV254, chroma and settlement height of PAFC at flocculant concentration of 60 g/L and solution pH of 6 were 72.2%, 79.2%, 82.9% and 9.5 cm (within 90 min), respectively. PAFC has excellent flocculation performance and can be used as a simple, potentially low-cost wastewater treatment agent in industrial applications.

scholarly journals Adsorption of Lead (II) from Aqueous Solution with High Efficiency by Hydrothermal Biochar Derived from Honey

2020 ◽  
Vol 17 (10) ◽  
pp. 3441 ◽  
Author(s):  
Bo Wang ◽  
Jie Yu ◽  
Hui Liao ◽  
Wenkun Zhu ◽  
Pingping Ding ◽  
...  
Keyword(s):  
Aqueous Solution ◽  
Photoelectron Spectroscopy ◽  
High Efficiency ◽  
Raw Material ◽  
Before And After ◽  
Initial Ph ◽  
Carboxylic Groups ◽  
Langmuir Isotherm Model ◽  
Pseudo Second Order ◽  
Natural Honey

A novel natural honey hydrothermal biochar (HHTB) was prepared using natural honey as raw material. The as-prepared adsorbent was applied to adsorb Pb2+ from aqueous solution and characterized by scanning electron microscopy, Fourier transform infrared spectroscopy, and X-ray photoelectron spectroscopy to investigate the structure and morphology change of the adsorbent before and after Pb2+ adsorption. The influence of the pH, initial Pb2+ concentration, temperature, and contact time on the adsorption of Pb2+ was systematically investigated. The results revealed that the adsorption capacity for Pb2+ is up to 133.2 mg·g−1 at initial pH of 5.0 and adsorption temperature of 298 K. Meanwhile, the adsorption of Pb2+ on HHTB can be well fitted by the pseudo-second-order model and Langmuir isotherm model. The adsorbent had great selectivity for Pb2+ from the aqueous solution containing coexisting ions including Cd2+, Co2+, Cr3+, Cu2+, Ni2+ and Zn2+. Furthermore, the adsorption of Pb2+ on HHTB was attributed to complexation coordination, where it involved hydroxyl and carboxylic groups on HHTB in the process of adsorption of Pb2+.

scholarly journals The Effect of Various Si/Al, Na/Al Molar Ratios and Free Water on Micromorphology and Macro-Strength of Metakaolin-Based Geopolymer

Materials ◽  
2021 ◽  
Vol 14 (14) ◽  
pp. 3845
Author(s):  
Hongguang Wang ◽  
Hao Wu ◽  
Zhiqiang Xing ◽  
Rui Wang ◽  
Shoushuai Dai
Keyword(s):  
Water Content ◽  
Mechanical Performance ◽  
Free Water ◽  
Raw Material ◽  
Current Work ◽  
Molar Ratio ◽  
Composition Analysis ◽  
Structural Water ◽  
Volume Stability ◽  
Molar Ratios

The current work aimed to explore the effect of Na/Al ratios of 0.43, 0.53, 0.63, 0.73, 0.83, and 0.93, using NaOH to alter the molar ratio, on the mechanical properties of a geopolymer material, with fixing of the Si/Al molar ratio. While fixing the Na/Al molar ratio, alteration of the Si/Al ratios to 1.7, 1.75, 1.8, 1.85, 1.9, 1.95 was used, with silica fume and sodium silicate as a silica corrector. The influence on the micromorphology and macro-strength of samples was characterized through SEM, EDS, and compressive strength characterization methods. The results show that Si/Al and Na/Al molar ratios play a significant role in the microstructure and mechanical behavior of MK-based geopolymers, and revealed that the optimal molar Si/Al and Na/Al ratios for attaining maximum mechanical strength in geopolymers are 1.9 and 0.73, respectively. Under various Si/Al ratios, the macro-strength of the geopolymer mainly relies on the formation of NASH gel, rather than zeolites or silicate derivatives. The appropriate Na/Al molar ratio can contribute to the geopolymerization, but a ultra-high Na/Al molar ratio caused a high alkali state that destroyed the microstructure of the geopolymers. Regardless of the amount of water contained in the initial geopolymer raw material, the water content of Si/Al = 1.65 and Si/Al = 1.75 after curing for 10 days was almost the same, and the bound water content of the final geopolymer was maintained at about 15%. Structural water exists in geological polymer gels in the form of a chemical structure. It has effects on the structural performance strength, while free water affects the volume stability of the geological polymer. Overall, the current work provides a perspective on the elemental composition analysis, combined with the molecular structure and micromorphology, to explore the mechanical performance of geopolymers.

scholarly journals Kinetics of Arsenic Removal in Waste Acid by the Combination of CuSO4 and Zero-Valent Iron

Processes ◽  
2019 ◽  
Vol 7 (7) ◽  
pp. 401 ◽  
Author(s):  
Yunhao Xi ◽  
Yongguang Luo ◽  
Jingtian Zou ◽  
Jing Li ◽  
Tianqi Liao ◽  
...  
Keyword(s):  
Arsenic Removal ◽  
Reaction Order ◽  
Kinetic Studies ◽  
Zero Valent Iron ◽  
Molar Ratio ◽  
Molar Ratios ◽  
Before And After ◽  
Shrinking Core ◽  
Kinetics Of ◽  
Waste Acid

In this study, we investigated the kinetics of arsenic removal from waste acid by the combination of zero-valent iron (ZVI) and CuSO4. ZVI samples were characterized by X-ray diffraction and scanning electron microscopy before and after arsenic removal; the results showed that after the arsenic removal reaction, As2O3 and magnetite phases were detected on the surface of these samples. Kinetic studies were carried out under different reaction temperatures, with different CuSO4 concentrations, and with different iron to arsenic molar ratios (Fe/As). The kinetic data of the arsenic removal were fitted to different kinetic models. The fitting results showed that the arsenic removal process could be described by the shrinking core model, controlled by residual layer diffusion. The apparent activation energy of the reaction was 9.0628 kJ/mol, the reaction order with the CuSO4 concentrations was −0.12681, and the reaction order with the molar ratio of iron to arsenic (Fe/As) was 3.152.

scholarly journals Synthesis of Zeolite A From Coal Fly Ash with Variation of Si/Al Molar Ratio

2018 ◽  
Vol 19 (2) ◽  
pp. 105
Author(s):  
Novita Andarini ◽  
Tanti Haryati ◽  
Zuhrotul Lutfia
Keyword(s):  
Fly Ash ◽  
Hydrothermal Treatment ◽  
Coal Fly Ash ◽  
Synthetic Zeolite ◽  
Raw Material ◽  
Molar Ratio ◽  
Zeolite A ◽  
X Ray ◽  
Molar Ratios ◽  
Aluminosilicate Mineral

Fly ash containing 30-36% silica and 14,52-23,78% alumina can be potentially as raw material for synthetic zeolite such as zeolite A. Zeolite A is an aluminosilicate mineral which is rich in alumina so that this zeolite has a good cation exchange capability. Zeolite A has been synthesized by hydrothermal treatment after NaOH fusion. Fly ash has been fused with NaOH at 550 0C for 40 minutes and hydrothermally treated at 1000C for 5 hours. The hydrothermal treatment was conducted in some various Si/Al molar ratios from 0.90; 1.00.; 1.05; to 1.24. The zeolite A was then analyzed using XRD and XRF. The best zeolite A based on XRD result is zeolite with Si/Al molar ratio of 1.1 with crystallinity of 96,80%. The x-ray fluorescence result showed that the Si/Al molar ratios of the four zeolite samples were close to of Si/Al molar ratios of 1, 1.1, 1.21.3 respectively.Keywords: Fly ash, Zeolite A, Hydrothermal Fusion

Interaction with Modified Cyclodextrin as a Way to Increase the Antimalarial Activity of Primaquine

2020 ◽  
Vol 17 (5) ◽  
pp. 670-681
Author(s):  
Liliane Henrique Torres ◽  
Lucas Bragança de Carvalho ◽  
Adneia de Fátima Abreu Venceslau ◽  
Carlos Jaime ◽  
Luciana de Matos Alves Pinto
Keyword(s):  
Antimalarial Activity ◽  
Molar Ratio ◽  
Release Time ◽  
Spatial Correlations ◽  
Scanning Calorimetry ◽  
Molar Ratios ◽  
Before And After ◽  
Important Challenge ◽  
Nmr Techniques ◽  
Hydrophilic Character

Background: Malaria is still a dangerous disease that impacts specifically Africa, Asia, and Latin America. The development of therapies to overcome the parasite infection is an important challenge nowadays. The medicine primaquine (PQ) is used in the treatment, although several side effects and low oral bioavailability are reported. Objective: This work focused on the preparation and characterization of a complex between PQ and 2- hydroxypropyl-β-cyclodextrin (HPCD), besides performing release tests of this formulation. Methods: PQ:HPCD complexes were prepared at 1:1 and 1:2 molar ratios, by the lyophilization method. The association between PQ and HPCD was tested using UV-vis, infrared (FTIR), differential scanning calorimetry (DSC), scanning electron microscopy and NMR techniques (chemical shift, Job Plot, DOSY, and ROESY). Tests were also conducted to evaluate drug release before and after complexation with HPCD. Results: Results showed that there was a weak interaction of PQ with HPCD, forming non-inclusion complexes. These results were supported by FTIR results and spatial correlations between hydrogens from PQ with the external HPCD hydrogens. A 1:2 PQ:HPCD preferred molar ratio was determined by DSC and Job Plot experiments and the time to release 96% of the drug was 21.2 h slower after complexation. Conclusion: Conclusion indicate that PQ interacts poorly with HPCD, probably due to its hydrophilic character, as well as to its interaction with the external rim of HPCD. Our results demonstrate that there was a significant improvement in the release time after the complexation process, which could lead to an increase in the activity of the drug.

Mango (Magnifera indica) seed oil grown in Dilla town as potential raw material for biodiesel production using NaOH- a homogeneous catalyst

2019 ◽  
Author(s):  
Chem Int
Keyword(s):  
Diesel Engine ◽  
Physicochemical Properties ◽  
Seed Oil ◽  
Methyl Esters ◽  
Pollution Prevention ◽  
Raw Material ◽  
Biodiesel Production ◽  
Molar Ratio ◽  
Homogeneous Catalyst ◽  
Minimal Amount

Biodiesel produced by transesterification process from vegetable oils or animal fats is viewed as a promising renewable energy source. Now a day’s diminishing of petroleum reserves in the ground and increasing environmental pollution prevention and regulations have made searching for renewable oxygenated energy sources from biomasses. Biodiesel is non-toxic, renewable, biodegradable, environmentally benign, energy efficient and diesel substituent fuel used in diesel engine which contributes minimal amount of global warming gases such as CO, CO2, SO2, NOX, unburned hydrocarbons, and particulate matters. The chemical composition of the biodiesel was examined by help of GC-MS and five fatty acid methyl esters such as methyl palmitate, methyl stearate, methyl oleate, methyl linoleate and methyl linoleneate were identified. The variables that affect the amount of biodiesel such as methanol/oil molar ratio, mass weight of catalyst and temperature were studied. In addition to this the physicochemical properties of the biodiesel such as (density, kinematic viscosity, iodine value high heating value, flash point, acidic value, saponification value, carbon residue, peroxide value and ester content) were determined and its corresponding values were 87 Kg/m3, 5.63 Mm2/s, 39.56 g I/100g oil, 42.22 MJ/Kg, 132oC, 0.12 mgKOH/g, 209.72 mgKOH/g, 0.04%wt, 12.63 meq/kg, and 92.67 wt% respectively. The results of the present study showed that all physicochemical properties lie within the ASTM and EN biodiesel standards. Therefore, mango seed oil methyl ester could be used as an alternative to diesel engine.

EFFICIENCY OF NEW HEMOSORBENT IN ACUTE AMITRIPTYLINE AND CYCLODOL POISONING

2020 ◽  
pp. 14-18
Author(s):  
A. M. Fomin
Keyword(s):  
Clinical Effect ◽  
High Efficiency ◽  
Initial Level ◽  
Synthetic Polymer ◽  
Complex Treatment ◽  
Direct Hemoperfusion ◽  
Selective Sorption ◽  
Positive Clinical Effect ◽  
Before And After

A complex treatment of a patient with acute amitriptyline and cyclodol poisoning using enterosorption, intestinal lavage and hemosorption on a new column with a synthetic sorbent is presented. A two-layer synthetic polymer column developed for the selective sorption of cytokines by direct hemoperfusion was used for hemosorption. Quantitative determinations of amitriptyline and cyclodol levels before and after the column, as well as before and after hemosorption have showed high efficiency of the sorbent to remove the toxicant from the blood. The use of 6-hour hemosorption allowed to reduce the level of amitriptyline from the initial level by more than 4 times and the level of cyclodol - by more than 3 times to therapeutic levels and to obtain a pronounced positive clinical effect in the complex treatment of a patient with severe poisoning.

scholarly journals Photocatalytic Reduction of CO2 to Methanol Using a Copper-Zirconia Imidazolate Framework

Catalysts ◽  
2021 ◽  
Vol 11 (3) ◽  
pp. 346
Author(s):  
Sonam Goyal ◽  
Maizatul Shima Shaharun ◽  
Ganaga Suriya Jayabal ◽  
Chong Fai Kait ◽  
Bawadi Abdullah ◽  
...  
Keyword(s):  
Photoelectron Spectroscopy ◽  
Catalyst Support ◽  
Oxidation Potential ◽  
Molar Ratio ◽  
X Ray Diffraction ◽  
X Ray ◽  
Molar Ratios ◽  
Optimum Parameters ◽  
Reduction Of Co2 ◽  
Enhanced Yield

A set of novel photocatalysts, i.e., copper-zirconia imidazolate (CuZrIm) frameworks, were synthesized using different zirconia molar ratios (i.e., 0.5, 1, and 1.5 mmol). The photoreduction process of CO2 to methanol in a continuous-flow stirred photoreactor at pressure and temperature of 1 atm and 25 °C, respectively, was studied. The physicochemical properties of the synthesized catalysts were studied using X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), and photoluminescence (PL) spectroscopy. The highest methanol activity of 818.59 µmol/L.g was recorded when the CuZrIm1 catalyst with Cu/Zr/Im/NH4OH molar ratio of 2:1:4:2 (mmol/mmol/mmol/M) was employed. The enhanced yield is attributed to the presence of Cu2+ oxidation state and the uniformly dispersed active metals. The response surface methodology (RSM) was used to optimize the reaction parameters. The predicted results agreed well with the experimental ones with the correlation coefficient (R2) of 0.99. The optimization results showed that the highest methanol activity of 1054 µmol/L.g was recorded when the optimum parameters were employed, i.e., stirring rate (540 rpm), intensity of light (275 W/m2) and photocatalyst loading (1.3 g/L). The redox potential value for the CuZrIm1 shows that the reduction potential is −1.70 V and the oxidation potential is +1.28 V for the photoreduction of CO2 to methanol. The current work has established the potential utilization of the imidazolate framework as catalyst support for the photoreduction of CO2 to methanol.

scholarly journals Lipozyme 435-Mediated Synthesis of Xylose Oleate in Methyl Ethyl Ketone

Molecules ◽  
2021 ◽  
Vol 26 (11) ◽  
pp. 3317
Author(s):  
Maria Carolina Pereira Gonçalves ◽  
Jéssica Cristina Amaral ◽  
Roberto Fernandez-Lafuente ◽  
Ruy de Sousa Junior ◽  
Paulo Waldir Tardioli
Keyword(s):  
Oleic Acid ◽  
Methyl Ethyl Ketone ◽  
Molar Ratio ◽  
Methyl Ethyl ◽  
Sugar Ester ◽  
Molar Ratios ◽  
Emulsion Capacity ◽  
Ping Pong ◽  
Commercial Sugar ◽  
Repeated Use

In this paper, we have performed the Lipozyme 435-catalyzed synthesis of xylose oleate in methyl ethyl ketone (MEK) from xylose and oleic acid. The effects of substrates’ molar ratios, reaction temperature, reaction time on esterification rates, and Lipozyme 435 reuse were studied. Results showed that an excess of oleic acid (xylose: oleic acid molar ratio of 1:5) significantly favored the reaction, yielding 98% of xylose conversion and 31% oleic acid conversion after 24 h-reaction (mainly to xylose mono- and dioleate, as confirmed by mass spectrometry). The highest Lipozyme 435 activities occurred between 55 and 70 °C. The predicted Ping Pong Bi Bi kinetic model fitted very well to the experimental data and there was no evidence of inhibitions in the range assessed. The reaction product was purified and presented an emulsion capacity close to that of a commercial sugar ester detergent. Finally, the repeated use of Lipozyme 435 showed a reduction in the reaction yields (by 48 and 19% in the xylose and oleic acid conversions, respectively), after ten 12 h-cycles.

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